1,720,960 research outputs found
Improved seismic design of structures using risk-targeting and cost-minimization considerations
Get PDFThis thesis was previously held under moratorium from 28th August 2020 until 30th August 2021.This thesis addresses various topics in the context of seismic design of structures with risk and loss considerations. Three design philosophies are investigated: the one based on uniform-hazard spectra, the risk-targeting technique, and an approach that minimizes the life-cycle costs. While the “uniform-hazard” approach is embedded in most of seismic design regulations, many studies have highlighted the need for a more rigorous and explicit control of the structural performance and of the consequences of seismic damage, not only at the assessment but also at the design stage. Thus, in this context, the risk targeting philosophy has emerged and has been implemented in US regulations. This approach is thoroughly reviewed herein, together with alternative risk-targeting techniques. Various case studies and European-wide investigations are performed to compare the results obtained with the risk-targeting and the uniform hazard approaches, evaluate the strengths and limitations of the techniques, and show possible steps forward. Acknowledging the significant financial implications of earthquakes, more advanced frameworks have been developed to account also for losses from future earthquake events in the design. A life-cycle cost optimization technique that considers the initial construction costs and the expected losses is studied in this work. A benchmark building is designed and analysed for different seismic levels and the results are compared against those obtained with the uniform-hazard and the risk-targeting approaches. Subsequently, an investigation is carried out on how the epistemic uncertainty inherent in seismic hazard models influences the structural design and the attained risk and loss estimates. The topic is investigated through different case studies, while a simplified approach for modelling hazard uncertainty is introduced and applied across Europe.In addition to constructing frameworks that mitigate losses, earthquake engineering can provide guidance to help manage the incurred loss levels. Thus, the last part of this thesis looks at the seismic risk management via the mechanism of transfer of financial risk. A method to define loss-informed insurance premiums is presented and various investigations across Europe are performed to explore efficient insurance strategies.This thesis addresses various topics in the context of seismic design of structures with risk and loss considerations. Three design philosophies are investigated: the one based on uniform-hazard spectra, the risk-targeting technique, and an approach that minimizes the life-cycle costs. While the “uniform-hazard” approach is embedded in most of seismic design regulations, many studies have highlighted the need for a more rigorous and explicit control of the structural performance and of the consequences of seismic damage, not only at the assessment but also at the design stage. Thus, in this context, the risk targeting philosophy has emerged and has been implemented in US regulations. This approach is thoroughly reviewed herein, together with alternative risk-targeting techniques. Various case studies and European-wide investigations are performed to compare the results obtained with the risk-targeting and the uniform hazard approaches, evaluate the strengths and limitations of the techniques, and show possible steps forward. Acknowledging the significant financial implications of earthquakes, more advanced frameworks have been developed to account also for losses from future earthquake events in the design. A life-cycle cost optimization technique that considers the initial construction costs and the expected losses is studied in this work. A benchmark building is designed and analysed for different seismic levels and the results are compared against those obtained with the uniform-hazard and the risk-targeting approaches. Subsequently, an investigation is carried out on how the epistemic uncertainty inherent in seismic hazard models influences the structural design and the attained risk and loss estimates. The topic is investigated through different case studies, while a simplified approach for modelling hazard uncertainty is introduced and applied across Europe.In addition to constructing frameworks that mitigate losses, earthquake engineering can provide guidance to help manage the incurred loss levels. Thus, the last part of this thesis looks at the seismic risk management via the mechanism of transfer of financial risk. A method to define loss-informed insurance premiums is presented and various investigations across Europe are performed to explore efficient insurance strategies
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Using targeted risk in seismic design codes : a summary of the state of the art and outstanding issues
No full textOver the past decade there have been various studies on the development of seismic design maps using the principle of “risk-targeting”. The basis of these studies is the calculation of the seismic risk by convolution of a seismic hazard curve for a given location (derived using probabilistic seismic hazard analysis) with a fragility curve for a code-design structure (ideally derived from structural modelling). The ground-motion level that the structure is designed for is chosen so that the structure has a pre-defined probability of achieving a certain performance level (e.g. non-collapse). At present seismic design maps developed using this approach are only applied in practice widely in the US but studies have also been conducted on a national basis for France, Romania and Indonesia, as well as for the whole of Europe using the European Seismic Hazard Model. This short article presents a review of the state of the art of this technique, highlighting efforts to constrain better some of the input parameters. In addition, we discuss the difficulties of applying this method in practice as well as possible paths forward
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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